The present invention relates to a fuel cell, and more particularly to an optical instrumentation system therefor.
There are several different general types of fuel cells which can be distinguished one from another primarily by the electrolytes they utilize. For example, there are fuel cells which utilize phosphoric acid, sulfuric acid, fluorinated phosphoric, sulfuric acid or the like acid electrolytes; ion exchange electrolytes; molten carbonate salt electrolytes; solid electrolytes such as doped zirconia or ceria; alkaline electrolytes; and other electrolytes which can be used in the electrochemical electricity-producing reaction. These fuel cells typically use hydrogen as the anode reactant and oxygen as the cathode reactant. However, other elements can be used, such as carbon for an anode reactant and air or chlorine for cathode reactants. The hydrogen will typically come from a fossil fuel which has been catalytically converted to a hydrogen-rich fuel gas, and the oxygen will come from air passed over the cathode side of the cell or cell stack.
Some fuels cells such as molten salt carbonate fuel cells have efficiencies as high as 70%. However, these fuel cells operate at high temperatures which may complicate thermocouple instrumentation of the fuel cell. At such high temperatures, thermocouples may have a relatively short lifespan. Should the thermocouples fail, information regarding the fuel cell operating conditions may become unavailable such that fuel cell may need to be shut down prior to the full lifespan of the fuel cell.
Accordingly, it is desirable to provide a reliable instrumentation system which operates at high temperatures for the full lifetime of the fuel cell.